TIMER_PT_ZERO

Severity: error

A TON / TOF / TP is set with PT := T#0s, or a constant that resolves to zero.

Why it matters. PT = 0 fires immediately on TON / TP (the delay is zero) or never on TOF (the off-delay is zero). Almost always the wrong intent.

Settings. No check-specific config.

PT recognition. PT is read from both standard call-arg style (T1(PT := T#0s)) and the B&R-style member assignment (T1.PT := T#0s; then T1();). The parameter name is matched case-insensitively in the default dialect, so pt := works the same as PT :=.

Trigger.

T1(IN := xEnable, PT := T#0s);     (* fires *)
T1.PT := T#0s; T1();               (* fires (member-assignment idiom) *)
T1(IN := xEnable, pt := T#0s);     (* fires (case-insensitive default) *)

The bot posts.

🟥 error  TIMER_PT_ZERO
Timer T1.PT resolves to T#0s (value: T#0s)
A PT of zero either fires immediately (TON/TP) or never (TOF on
falling edge), neither of which is usually intended.

Fix. Set a non-zero PT.